ATAN2 Function -> Return Bounds

[TLSmith]

The ANSI book describes the ATAN2 return as bounded from -pi to +pi. CVI version 5 is giving me what appears to be 0 to 2*pi. What could be going on?

[SachaE]

Hi,
I've not got CVI 5 to hand, but under CVI 6, it seems fine - brought up the panel for ATAN2 and entered the following pairs.
-2 -2 -> -2.35619 bottom left quadrant =-135 deg
-2 2 -> -0.785398 bottom right quadrant =-45 deg
2 -2 -> 2.35619 top left quadrant = +135 deg
2 2 -> 0.785398 top right quadrant = +45 deg

which is as expected. Might be worth contacting your local NI branch (or going via http://www.ni.com/ask to the ask an engineer page)

S.